1. Field of the Invention
This invention relates to synthetic resin electrical junction and switch boxes which include easily removable break-out panels or windows facilitating extension of electrical conductors through openings thus formed in side walls of the box, and which further provide spring metal clips in association with screw holes and facilitating rapid and easy securement of a cover plate over the open side of the box by means of threaded fastening elements.
2. Brief Description of the Prior Art
An improved synthetic resin electrical junction and switch box susceptible to construction by a one-shot, two-part molding process is described in Donald G. Copp U.S. Pat. No. 3,773,968 assigned to the assignee of the present invention. The synthetic resin box described in the Copp application works very well in practice, and can usually be constructed with no difficulty by a one-shot molding process. Where some types of plastic materials are employed in molding the box, however, some difficulty has been encountered in obtaining accurate molding of the knockout panels or windows formed in such boxes in a way such that the required spacing or separation of these windows or panels from the remainder of the box is attained.
Another type of synthetic resin electrical junction and switch box is described in our U.S. Pat. No. 3,895,732 issued July 22, 1975, and assigned to the assignee of the present invention. The synthetic resin box described in the latter patent includes integrally molded break-out windows or panels which are formed to lie in a plane which extends at an acute angle to two adjacent sides of the box and is surrounded by a gap or space separating it from the surrounding portions of the box. Two bridge webs hold the panel in position in the window opening and extend between adjacent sides of the box, and a pair or parallel guide ribs are provided on the inside surface of such removable panel. This construction assures that the panel or window can be easily pushed out from the side of the box by directing a screwdriver against the inside surface of the panel or window at such time as it is desired to extend electrical conductors from the outside to the inside of the box through the openings thus formed.
Another feature of the electrical junction and switch box described in our U.S. Pat. No. 3,895,732 is the inclusion of spring metal clips adjacent screw holes formed in, or adjacent, the side walls of the box, so that a cover or closure plate can be quickly and easily secured across the open side of the box, following completion of the electrical connections thereto, by the use of threaded screws or similar fasteners engaged with the clips.